Flight Time Calculation

[Aire de Drome]

I was told many moons ago that flight times were calculated from 'chocks away' to 'chocks under' at the end of the flight. Is this correct? If not I would appreciate an explaination, save me from scratching my head. Many thanks. AdD

[xtypeman]

Blocks off to Blocks on is one time but there is also airborne to landing. Airborne to landing is considered as flight time.

[DaveReidUK]

Yes, "flight time" is an ambiguous expression and can have different meanings depending on the context.

Best advice is simply not to use the term. As mentioned above, "block time" is measured from gate (ATD) to gate (ATA). On the other hand, if you're only interested in the part from takeoff to landing, you might be better off using the term "flying time" as that is normally taken to mean only the airborne part of a flight.

[Hotel Tango]

If you are referring to so-called flight times in published airline schedules, they are block times (gate to gate).

[wiggy]

As others have said it depends on the context.

Timetable "flying time" is generally brakes off at the start of the flight to brakes on at the end, probably in part because the paying passenger knows when he/ she is going to be getting on/ off the aircraft.

In most jurisdictions civilian pilots use the same definition for logging flying times in their logbooks - OTOH the military often log the time from take-off to landing..........

And most pilots mean the airborne time when the refer to "flying time" in their on-board announcements.......

All clear now????

[+TSRA]

Air Time: The time between when the aircraft leaves the surface of the earth until it comes into contact with the ground on landing.

Flight Time: From when the aircraft first moves under its own power for the purpose of take-off until it stops at the conclusion of the flight.

Airtime is thus the time the aircraft is aloft, while flight time is the "blocks to "blocks" as some people call it.

Airlines tend to use flight time because that's how long you will be sitting in the airplane for. It's also the one pilots log. It's not uncommon to see 1 hour air time with 1.5 flight time because of long taxi, waiting for other aircraft to takeoff or land, etc. Hence, airlines tell you the 1.5 hour flight time. That way, if they do it in 1.3 they look better!

[One Outsider]

Now you are just confusing the issue further. As others have already said, the meaning of "flight time" is context related.

[DaveReidUK]

Flight Time: From when the aircraft first moves under its own power for the purpose of take-off until it stops at the conclusion of the flight.In most cases, the above doesn't actually define anything.

Block time starts as soon as the aircraft moves from the gate, i.e. when the brakes are released and the pushback begins (the "Out" time in ACARS parlance).

The next recorded time will be when the wheels leave the runway (the ACARS "Off" time).

Obviously at some stage in between the Out and Off times, the tractor/towbar will be disconnected and the aircraft will start to move under its own power, but that event isn't used in the calculation of either flight or block time.

[One Outsider]

Dave, you appear to be another office expert. Block time starts when the company defines it does. It may be when the aircraft first moves or when the aircraft first moves under its own power.

The OOOI times are purely technical and companies are free to use them as they see fit.

[parabellum]

Have never thought the terms to be ambiguous really, Block Time is chock to chock, whether a push back is involved or not and flight time is wheels leaving the ground until they touch again. For the purpose of the pilot's log book the loggable time is usually from the moment the aircraft moves under it's own power until the chocks go in and engines are shut down at destination.

[+TSRA]

One Outsider,

I'm not certain the regulatory (sorry "office expert") terms cloud the issue at all. Air time is air time and flight time is flight time. Pretty simple. It may be context related, but the OP question was specific enough to justify using industry terms.

Also, it's only the Out and In times which are at the discretion of the airline (push back or start). The Off and On times are not discretionary as they immediately impact any maintenance items which are air time dependant.

I digress, as this is way off the original topic which is whether block to block is "flight time?" Yes it is.

[DaveReidUK]

Dave, you appear to be another office expert. Block time starts when the company defines it does.'When I use a word,' Humpty Dumpty said, in rather a scornful tone, 'it means just what I choose it to mean - neither more nor less.'

[Aire de Drome]

Thanks, everyone. Excellent. I'm now going back to the beginning to read it all again...

[Dave Gittins]

As any good lawyer will tell you "it all depends".

If you are recording times for regulatory purposes such as pilot, airframe or engine hours for pilot qualifications and times between overhaul or for component lifeing, there are specific regulations set out for each case by the authorities (and plenty of people willing to argue over the interpretation :ugh:).

If you are an airline advertising how long it takes to get from A - B, it most likely is from pushback to brakes on but an airline is free to use any measure it likes as long as it isn't grossly misrepresenting the position.

DGG :ok: